Endless drive system

ABSTRACT

An endless drive system suitable for use, for example, as a tracked vehicle drive system, an endless belt or an endless chain drive system. A number of endless drive sections are interconnected by cable connector sections. The cable connector sections include cables which can be encased in rubber. The cables can be provided with end retaining members which aid in retaining the cable connector sections and the endless drive sections together and which prevent expanding, fraying or unwinding of the cable ends. Special end retaining members can be utilized to aid self-alignment of the system.

CROSS REFERENCE TO RELATED APPLICATION

This is a division of application Ser. No. 607,067 filed May 4, 1984,now U.S. Pat. No. 4,569,561, which was a continuation-in-part ofapplication Ser. No. 516,831, filed July 25, 1983 and now abandoned.

BACKGROUND OF THE INVENTION

The present invention pertains to an endless drive system. Moreparticularly, the present invention pertains to an endless drive systemsuitable for use as a tracked vehicle drive system in a vehicle such asa tractor, bulldozer or tank, for use as an endless belt, or for use asan endless chain drive. By way of example, an endless drive system inaccordance with the present invention might be used on a tractor of acrop harvesting apparatus of the type disclosed in Edwards U.S. Pat. No.4,202,158, issued May 13, 1980.

U.S. Pat. No. 4,093,318, issued June 6, 1978 to John W. Edwards, thedisclosure of which is incorporated herein by reference, describes andclaims an endless drive system including a plurality of endless drivesections, each having a substantially flat contact surface and slopedsurfaces to distribute weight and shed dirt and other foreign objects.Pivotal means of connecting these endless drive sections enable themovement of the endless drive system in an endless path. It has beenfound that dirt and foreign objects still cause some difficulties withthe endless drive system of U.S. Pat. No. 4,093,318, particularly whenused as the drive system of a tracked vehicle.

SUMMARY OF THE INVENTION

The present invention concerns improvements on the endless drive systemof Edwards' U.S. Pat. No. 4,093,318, particularly improvements on thepivotal means of connecting the endless drive sections. In a preferredembodiment of the present invention, the endless drive system is made upof a number of endless drive sections interconnected by cable connectorsections. Preferably, these cable connector sections include cablesencased in rubber or other suitable material, and the combination of thecable and the encasing material provides both elasticity, assuringsufficient flexibility to permit the drive system to move in an endlesspath, and tensile strength, necessary to retain the endless drivesections together as an endless drive system.

The cables which interconnect the endless drive sections provide greatstrength and reliability, with minimum noise and with considerablefreedom from maintenance. By encasing the cables in, for example,rubber, the present invention prevents dirt from accumulating and fromdetrimentally affecting the cables. Consequently, the shield portionutilized in the endless drive system of U.S. Pat. No. 4,098,318 isunnecessary, and yet the system of the present invention is adaptable toa wide range of environments, including sand, mud, and hazardousenvironments such as fire fighting. Further, the rubber reduces thenoise of the endless drive system. In accordance with the presentinvention, the cables are preferably provided with end retaining memberswhich aid in retaining the cable connector sections and the endlessdrive sections together as an endless drive system and which preventexpanding, fraying, or unwinding of the cable ends. These end retainingmembers might also aid in self-alignment of the cable connector sectionsand thus of the overall endless drive system.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other aspects and advantages of the present invention are moreapparent in the following detailed description and claims, particularlywhen considered in conjunction with the accompanying drawings in whichlike parts bear like reference numerals. In the drawings:

FIG. 1 is a perspective view of a tractor equipped with a pair ofendless drive systems in accordance with the present invention;

FIG. 2 is a fragmentary perspective view, partially broken, illustratingan endless drive system in accordance with the present invention;

FIGS. 3 through 7 are elevational views depicting various embodiments ofendless drive sections and various embodiments of cable connectorsections each of which is suitable for incorporation in an endless drivesystem in accordance with the present invention;

FIGS. 8 through 17 depict various embodiments of cables and cable clampssuitable for incorporation in an endless drive system in accordance withthe present invention;

FIG. 18 is a front elevational view of a wheel suitable forincorporation in an endless drive system in accordance with the presentinvention;

FIG. 19 is a sectional view taken along line 19--19 of FIG. 18;

FIG. 20 depicts a further embodiment of an endless drive system inaccordance with the present invention;

FIG. 21 is an elevational view of several endless drive sectionsconnected together in accordance with another embodiment of the presentinvention;

FIG. 22 is a sectional view along lines 22--22 of FIG. 21;

FIG. 23 is a fragmentary view taken along line 23--23 of FIG. 21;

FIG. 24 is a perspective view of a wheel suitable for use with the drivesections of FIG. 21;

FIG. 25 is an elevational view of two endless drive sections connectedtogether in accordance with a further embodiment of the presentinvention;

FIG. 26 is a perspective view of a wheel suitable for use with the drivesections of FIG. 25;

FIG. 27 is a sectional view through a wheel and drive section of anotherembodiment of the present invention;

FIG. 28 is a perspective view of a tool useful with the endless drivesystem; and

FIG. 29 is a perspective view of a tractor equipped with a pair ofendless drive systems in accordance with another embodiment of thepresent invention.

DETAILED DESCRIPTION OF SOME PREFERRED EMBODIMENTS

A preferred use of the endless drive system of the present invention isas a drive system for a tracked vehicle such as tractor 20 depicted inFIG. 1. As there depicted, tractor 20 is equipped with two endless drivesystems 22. Each endless drive system 22 is made up of a number ofendless drive sections 24 which are joined together by cable connectorsections 26 in a closed loop to form the endless drive systems 22.Tractor 20 includes the necessary power source and controls to permitendless drive systems 22 to propel the tractor over terrain as desired.

Each endless drive system 22 passes about a number of wheels includingend wheels 28, and idler wheels or rollers 29. While FIG. 1 depictsthree idler wheels 29 on each side of tractor 20, the number of centralwheels utilized depends upon the size of the tractor, the size of thewheels, and the size of the endless drive system 22. At least one of thewheels 28 or 29 for each endless drive system 22 of tractor 20 ispowered by an engine or other suitable power source.

FIG. 2 depicts a number of endless drive sections 24a joined together bya number of cable connector sections 26a in accordance with a firstembodiment of the present invention. For clarity and to permit showingof detail, in FIG. 2 the cable connector section 26a which would connectthe front endless drive section 24a to the section 24a in front of ithas been omitted. In practice, several endless drive sections 24a andcable connector sections 26a would be utilized to form an endless drivesystem. Each endless drive section 24a is formed of a rigid frame whichincludes a substantially closed shoe portion 30a having first and secondside edges, first and second substantially closed side walls 32aextending from the first and second side edges of the shoe portion 30aand sloping inwardly therefrom toward the center of the endless drivesystem, and closed central surface 34a joining the first and second sidewalls 32a. Shoe portion 30a, the two side walls 32a, and central surface34a thus define a chamber 36 open at its front and rear end faces.

Each contiguous pair of endless drive sections 24a is coupled togetherby a cable connector section 26a. Thus, each cable connector section 26ais fastened, for example by a first pair of bolt and nut fasteners 38,to the shoe portion 30a of one endless drive section 24a and by a secondpair of bolt and nut fasteners 40 to the shoe portion 30a of theadjacent endless drive section 24a. Accordingly, the plurality ofendless drive sections 24a is joined together by the like plurality ofcable connector sections 26a to form an endless drive system.

As depicted in FIGS. 1 and 2, the sloping side walls 32a of each endlessdrive section 24 preferably taper inwardly from a wider dimension alongthe lower edges thereof at shoe portion 30a to a narrower dimension atcentral surface 34a. This taper aids in the flexing of the endless drivesystem as it moves about end wheels 28. As also depicted in FIG. 2, eachendless drive section 24a is preferably provided with a tread member 42which might include a grouser 43 and which is fastened to shoe portion30. Further, wear pads 44 are preferably fastened to the sloping sidewalls 32a, and wear pad 46 is preferably fastened to central surface34a. These wear pads might be formed of rubber such as 80 durometerrubber with a steel contact plate on the surface abutting the side walls32a and the central surface 34a. Thus, typical wear pads 44 and 46 mightbe one inch of 80 durometer rubber on a one-fourth inch steel plate.Alternatively, the wear pads could be a synthetic material, for examplea polyurethane or other plastic, or for hazardous use such as on a firefighting vehicle the wear pads could be steel. The wear pads 44 and 46can be attached, for example, by means of bolts 48 which pass throughcountersunk openings 50 in the wear pads and mate with nuts 52 or withthreaded openings in the walls 32a and surface 34a. The wear pads 44 and46 and the tread members 42 prolong the life of the endless drivesections, in that when the wear pads or tread members are worn, theirreplacement renews the endless drive sections.

In the embodiment depicted in FIG. 2, each cable connector section 26aincludes two cable clamps 54a with a plurality of multistrand cables 56aextending between them. The two cable clamps 54a and the cables 56a areencased within resilient housing 58a which, for example, can be rubber.One end of each cable connector section 26a is fastened to a firstendless drive section 24a by bolt and nut fasteners 38, with the boltspassing through the shoe portion 30a of that section 24a, through rubberhousing 58a, and through a first one of the cable clamps 54a. The secondend of each cable connector section 26a is connected to the adjacentendless drive section 24a by bolt and nut fasteners 40, with the boltspassing through the shoe portion 30a of that section 26a, through rubberhousing 58a, and through the second cable clamp 54a.

Rubber housing 58a can be molded about the two cable clamps 54a andcables 56a, with the openings for passage of the bolts of bolt and nutfasteners 38 and 40 formed during the molding process. Such techniquefirmly grips the cables. Cable clamps 54a fit tightly about the ends ofcables 56a to hold the cables rigidly.

Endless drive sections 24 and cable connector sections 26 can take anyof several configurations. FIG. 2 depicts each of these as truncatedtriangular sections, with cable connector sections 26a being slightlynarrower than the open chamber 36 so that a small space exists on eachside of cable connector sections 26a to enable any dirt or other foreignobjects which might enter to fall freely from open chamber 36 as theendless drive system operates.

FIGS. 3 through 7 illustrate a number of alternative embodiments ofendless drive sections 24 and of cable connector sections 26, althoughadditional alternative embodiments are also possible within the scope ofthe present invention. FIG. 3 depicts endless drive section 24b of atriangular shape and cable connector section 26b of rectangular shape.FIG. 4 depicts endless drive section 24c of a truncated triangular shapesimilar to that of sections 24a of FIG. 2, but shows cable connectorsection 26c of a low rectangular shape, just sufficient to fully encasethe cable clamps and cables. FIG. 5 depicts triangular endless drivesection 24d with a triangular cable connector section 26d fitting snuglyagainst the inner surfaces of the sloping side walls 32d. Triangularcable connector section 26d fills most of the chamber 36 of endlessdrive section 24d, having only enough room beneath the central surface34d for the bolt and nut fasteners 38 and 40. The rubber portion ofcable connector section 26d is preferably provided with one or moreholes 60 to increase the flexibility of the cable connector section.FIG. 6 depicts an endless drive section 24e with sloping side walls 32ejoined by rounded or curved central surface 34e. FIG. 6 also depicts atruncated triangular cable connector section 26e having a hole 62therethrough to increase flexibility. FIG. 6 also depicts the bolt andnut fasteners 38 as including washers 64 to increase the area of contacton the upper surface of the rubber housing 58e. FIG. 7 depicts endlessdrive section 24f of a generally truncated triangular shape but with theshoe portion 30f thereof extending beyond the sloping side walls 32fthereof to provide flanges 66. Rubber wear pads are fastened to sidewalls 32f and abut against the flanges 66. If desired, the rubberhousings 58f or the side wall wear pads 44 can be contoured to include arib so that as the endless drive sections curve around end wheels 28,the ribs fill any voids between the side walls 32 of adjacent drivesections 24, providing a substantially smooth surface. Rubber wear pads,such as pads 44 and 46 of FIG. 2, can be utilized with any of theendless drive sections of FIGS. 3 through 6 as well. It is thus seenthat the endless drive sections and the cable connector sections canhave any of numerous configurations in accordance with the presentinvention, some of which are depicted in detail in FIGS. 2-7.

Likewise, the cable clamps 54 and cables 56 can have any of severalconfigurations. FIG. 8 depicts two cable clamps, each formed of twohalves 54b, held together by bolt and nut fasteners 55, with one cableclamp being on each end of each of a plurality of cables 56b. Each cableclamp half 54b has a number of recesses on its interior surface forreceipt of the cables.

FIG. 9 depicts a cable 56c having a spherical retaining member or button70c on each end. FIG. 10 depicts a corresponding cable clamp half 54chaving in its interior surface a number of recesses, each of whichincludes a channel opening 67c and terminates in a hemispherical recess68c so that when two cable clamp halves 54c are clamped on the ends of aset of cables 56c, the spherical retaining members 70c are firmlygripped within the recesses 68c of the two cable halves 54c to retainthe cables 56c within the cable clamp. Spherical retaining members 70ccan move within the hemispherical recesses 68c to align cables 56c andthe cable clamping system as required.

FIGS. 11 and 12 depict an alternative form of cable 56d and cable clamphalf 54d. Each cable 56d has a retaining member or button 70d encirclingeach end, and each cable clamp half 54d has a recess on its interiorsurface, including a channel opening 67d and terminating inhemispherical recess 68d for gripping the retaining members 70d.

FIGS. 13, 14, and 15 depict a further embodiment of cable 56e and cableclamp halves 54e. Each cable 56e has an annular retaining member orbutton 70e encircling the cable adjacent each end thereof. The cableclamp halves 54e have recesses 67e in the form of channel openingspassing therethrough so that, as depicted in FIG. 14, each cable 56eextends completely through the clamp, with retaining members 70e outsidethe clamp but preventing the cables 56e from being pulled from theclamp. In addition to retaining the cables within the cable clamps, theretaining members 70c, 70d, and 70e prevent expanding, fraying, orunwinding of the cable ends.

FIG. 16 depicts another preferred form of cable 56f having retainingmembers or buttons 70f on each end. Each retaining member 70f is a mildsteel cylinder, tapered on its inner end, which is slipped over the endof cable 56f and squeezed or swaged to fit tightly over the cable end.The mating cable clamp halves 54f, depicted in FIG. 17, have recesses67f to receive and retain members 70f. The mild steel retaining members70f are sufficiently deformable that recesses 67f can be formed as cableclamp halves 54f are molded, rather than by machining. Retaining members70f are of a length that results in only a short portion of cable 56fbeing exposed, for example about one inch. The taper of the inner endsof retaining members 70f acting on the corresponding ends of recesses67f causes the retaining members to be more tightly clamped aroundcables 56f as force is exerted on the cables during operation.

Each cable clamp half 54 has a first set of openings 72 therethrough forbolt and nut fasteners 55, which fasten the cable clamp halves togetherabout the ends of the cables 56, and a second set of openings 74 forbolt and nut fasteners 38 and 40. Alternatively, the lower cable clamphalves 54 can be cast or otherwise formed as a part of contact surface30 with openings 72 therethrough.

The cable clamps 54 and cables 56 of FIGS. 8-17 can be encased within aresilient housing 58 as depicted in FIGS. 2-7. Alternatively, theendless drive sections 24 can be joined by cable connector sectionsformed only by cable clamps 54 and cables 56, with no resilient housing.Thus, for example, each cable connector section can be formed of cableclamps and cables of the type depicted in FIG. 8 or FIG. 14. The cables56b or 56e can be bare or can be coated with rubber or other resilientmaterial, as desired.

As can be seen from FIGS. 2 through 7, the endless drive sections havesloping side walls 32 and so their width varies from a maximum at theshoe portion 30 to a minimum at the central surface 34. FIGS. 18 and 19depict a wheel 28' suitable for use as a drive wheel in an endless drivesystem in accordance with the present invention. Wheel 28' includesfirst and second side portions 76, each of which can have asubstantially flat exterior surface 78 and an interior surface 80 slopedat an angle to match the angle of the sloping side walls of the endlessdrive sections 24. Central portion 82 connects the two side portions 76of wheel 28'. As can be seen particularly from FIG. 19, the slopedinterior surfaces 80 are formed of a number of wedges, each wedge beingshaped to match the corresponding side wall of the endless drivesections that are to be utilized with the wheel 28'. Thus, theembodiment of wheel 28' depicted in FIGS. 18 and 19 has a number ofwedges 84 of a truncated triangular shape, matching the truncatedtriangular shape of the side surfaces of endless drive sections 24a ofFIG. 2. Endless drive sections 24b and 24d of FIGS. 3 and 5 requirewheels having triangular wedges. The number of wedges 84, as well as theshape and size of those wedges, is determined by the central angle ofthe endless drive section and the dimensions of the endless drivesection side walls. Typically, wheel 28' might have a diameter in theorder of about 36 inches or about 48 inches. If only one end wheel 28 isa drive wheel, the other end wheel can be rounded to receive the endlessdrive sections rather than being configured like drive wheel 28' ofFIGS. 18 and 19. Likewise, idler wheels 29 need not be configured likedrive wheel 28' but instead can be rounded. Alternatively, idler wheels29 could be smaller and positioned at points to support the endlessdrive sections 24 in straight upper and lower runs.

FIG. 20 depicts an endless drive system for very light duty such as alight duty vehicle or an endless conveyor. The cables 56g and the cableclamps 54g are fastened by bolt and nut fasteners 38 directly to theshoe portion 30g. Thus, the endless drive section 24g do not have sidewalls or central surfaces, and the cable connector sections 26g do notinclude rubber housings. The cables 56g can be bare or can be coatedwith rubber or other suitable material, depending upon the environmentin which the endless drive system is to be used.

For heavy duty use, cables 56 are preferably steel cables. For lightduty, other materials can be used, for example, nylon or other highstrength, light weight cord. Likewise, while the drawings have shown thecable connector sections 26 as having discrete pieces of cable,continuous cables extending the entire length of the endless drivesystem and fastened by the cable clamps 54 to each endless drive section24 could be utilized. When used on a tractor as shown in FIGS. 1 and 28,preferably the cable members are long enough to provide a space of aboutone inch between adjacent endless drive sections.

A further embodiment of the invention can be seen in FIGS. 21 through23. FIG. 21 is a side elevational view of a series of endless drivesections 101 joined together by connector sections 103. As seen in FIG.22 each drive section includes a grouser bar 105 having a portion 107extending laterally beyond the closed shoe portion 109. Grouser bar 105has a boss plate 111 formed integrally therewith, and boss plate 111 hasgrooves 113 formed therein, extending in the longitudinal direction ofthe overall endless drive system. The closed shoe portion 109 is made inthe form of an A-frame including first and second trapezoidal side walls115, which slope inwardly toward the center of the endless drivesection, and cable clamp bar 117. Cable clamp bar 117 has grooves 119formed therein which cooperate with grooves 113 in boss plate 111 toclamp the cables of connector sections 103 therebetween. Cable clamp bar117 has apertures to receive nut and bolt arrangements 121 for clampingboss plate 111 to cable clamp bar 117 to hold the cable connectorsection 103. Cables 56f of FIG. 16 are particularly suited for use withcable clamp bar 117 and boss plate 111.

Laterally extending portion 107 has holes 123 therethrough to allow dirtto fall away so that it does not interfere with the working of theapparatus. The endless drive sections 101 are provided with wear pads125 and 127.

As seen in FIG. 24, drive wheel 140 can be made of side portions 142each including a plurality of wedge-shaped sectors 146 with rounded bars148 between adjacent sectors 146. The rounded bars 148 interfit betweenthe adjacent endless drive sections 101 to provide positive engagementtherewith for driving the endless drive system from the drive wheel 140.As can be appreciated from FIGS. 22 and 24, the laterally extendingportions 107 of a plurality of sections 101 form a side rail on whichthe peripheral edges of side portions 142 of wheel 140 and similar idlerwheels rest, improving the weight distribution of the drive wheel andidler wheels on the endless drive sections. As seen particularly in FIG.23, the wear pads 127 are preferably made to lap over two adjacent drivesections 101.

FIGS. 25 and 26 depict respectively an embodiment of an endless drivesection 150 having drive pins 152 extending from the top thereof and anembodiment of a drive wheel 154 having spaced recesses 156 to receivethe drive pins 152 to provide positive engagement between wheel 154 andsections 150.

FIG. 27 discloses a further embodiment of the invention in which anendless drive section 160 has a concave drive surface 162. Preferablysurface 162 is made up of flat surfaces 164 and 166 which meet at anobtuse angle. In this embodiment the drive wheel 168 has a convex outerprofile adapted to cooperate with the concave drive surface 162 of thedrive section. The flat surfaces 164 and 166 are provided with wear pads170, and the endless drive sections 160 are joined to adjacent sectionsby connector sections 172.

FIG. 28 shows a tool which is particularly useful with the embodiment ofFIG. 26, but may also be used with the other embodiments. A V-shapedscraper blade 173 is supported by a bracket 174 which can be affixed tothe side of the tractor or to some other supporting surface to scrapedirt or other foreign material from the surfaces 164 and 166 to preventsuch foreign material from abrading or in other ways interfering withthe operation of the endless drive system.

FIG. 29 shows a tractor 180 equipped with endless drive systemsaccording to another embodiment of the invention. In this case, thegrouser bars 182 are provided in the shape of a chevron, with the convexangle pointing toward the forward direction of motion of the tractor.Thus, as the grouser bars 182 of an endless drive system turn around aforward wheel 184, the apex of the chevron digs into ground 186 toenhance the traction of the endless drive system.

It is thus seen that in accordance with the present invention animproved endless drive system is provided. Although the presentinvention has been described with reference to preferred embodiments,numerous rearrangements and alterations could be made, and still theresult would be within the scope of the invention.

What is claimed is:
 1. An endless drive system comprising:a plurality ofendless drive sections each including a substantially closed shoeportion having first and second side edges, first and secondsubstantially closed side walls extending from the first and second sideedges of the shoe portion and sloping inwardly therefrom toward thecenter of the endless drive section, and a central surface joining thefirst and second side walls to define therewith and with the shoeportion a drive section body; and a like plurality of cable connectorsection, each including at least one cable member and means to attachone end of the cable connector section to a first one of the endlessdrive sections and the other end of the cable connector section a secondone of the endless drive sections, such attachments being within thedrive section bodies of the endless drive sections, to cause theplurality of cable connector sections to join the plurality of endlessdrive sections in a closed loop as an endless drive system.
 2. Anendless drive system as claimed in claim 1 in which each cable connectorsection attaching means comprises a first cable clamp fastened to eachcable member of the cable connector section, a second cable clampfastened to each cable member of the cable connector section, means forfastening the first cable clamp to the first one of the endless drivesections and means for fastening the second cable clamp to the secondone of the endless drive sections.
 3. An endless drive system as claimedin claim 2 in which each cable clamp comprises a pair of cable clamphalves and means for fastening the pair of cable clamp halves togetheron the corresponding cable members.
 4. An endless drive system asclaimed in claim 3 in which each cable clamp half includes at least onerecess for receipt of the at least one cable member.
 5. An endless drivesystem as claimed in claim 4 in which each cable member is a discretecable piece extending from the first cable clamp to the second cableclamp.
 6. An endless drive system as claimed in claim 5 in which eachcable piece has a retaining member on each end thereof.
 7. An endlessdrive system as claimed in claim 6 in which the cable clamp recesses areshaped to permit passage of the cable members through the cable clampand the retaining members are positioned outside the cable clamp toprevent the cable from pulling out of the cable clamps.
 8. An endlessdrive system as claimed in claim 7 in which the cable clamp recesses areshaped to receive and retain the retaining members within the cableclamp.
 9. An endless drive system as claimed in claim 1 in which eachcable connector section further includes a resilient housing encasingthe at least one cable and the attaching means.
 10. An endless drivesystem as claimed in claim 1 in which said cable member has sufficientlength to provide a space of about one inch between shoe portions ofadjacent endless drive sections.
 11. An endless drive system as claimedin claim 1 in which said means to attach the ends of the cable connectorsections to the endless drive sections is a cable clamp bar integralwith said first and second side walls.
 12. An endless drive system asclaimed in claim 11 in which said cable clamp bar and said shoe portionhaving opposed complementary grooves to receive said cable member. 13.An endless drive system as claimed in claim 1 in which each cable memberof each cable connector section is integrally formed with a cable memberof each adjacent cable connector section to provide a continuous cablejoining the plurality of endless drive sections in a closed loop as anendless drive system.
 14. An endless drive system as claimed in claim 13in which each cable connector section attaching means comprises a pairof cable clamp halves and means for fastening the pair of cable clamphalves together on the corresponding cable members.
 15. An endless drivesystem as claimed in claim 14 in which each cable clamp half includes atleast one recess for receipt of the cable member.
 16. An endless drivesystem as claimed in claim 15 in which each cable piece has a retainingmember on each end thereof.
 17. An endless drive system as claimed inclaim 16 in which the cable clamp recesses are shaped to permit passageof the cable members through the cable clamp and the retaining membersare positoned outside the cable clamp to prevent the cable from pullingout of the cable clamps.
 18. An endless drive system as claimed in claim16 in which the cable clamp recesses are shaped to receive and retainthe retaining members with the cable clamp.
 19. An endless drive systemas claimed in claim 13 in which each cable connector section furtherincludes a resilient housing encasing the at least one cable member andthe attaching means.
 20. An endless drive system as claimed in claim 13in which said cable member has sufficient length to provide a space ofabout one inch between shoe portions of adjacent endless drive sections.21. An endless drive system as claimed in claim 13 in which said meansto attach the ends of the cable connector sections to the endless drivesections is a cable clamp bar integral with said first and second sidewalls.
 22. An endless drive system as claimed in claim 21 in which saidcable clamp bar and said shoe portion have opposed complementary groovesto receive said cable member.
 23. An endless drive system as claimed inclaim 13 in which said shoe portion extends beyond said first and secondside walls.